update statistics有三种级别，LOW：搜集了关于column的最少量信息，只更新部分统计信息；HIGH：进行全部统计信息的更新；MEDIUM：抽样选取数据分布信息。考虑到速度性能因素，以下对更新级别选择合适的有：（）A、对整表执行：update statistics lowB、对每个索引中的第一个字段执行：update statistics highC、对复合索引执行：update statistics mediumD、必要时对非索引、但在条件中使用到的字段执行Update statistics high
update statistics有三种级别，LOW：搜集了关于column的最少量信息，只更新部分统计信息；HIGH：进行全部统计信息的更新；MEDIUM：抽样选取数据分布信息。考虑到速度性能因素，以下对更新级别选择合适的有：（）
- A、对整表执行：update statistics low
- B、对每个索引中的第一个字段执行：update statistics high
- C、对复合索引执行：update statistics medium
- D、必要时对非索引、但在条件中使用到的字段执行Update statistics high
相关考题：
You are the administrator of SQL server 2000 computer. The server contains a database named MedicalRecords. Users access medical records by using the PatientID field. This field is the clustered primary key for the Patients table. When users try to access medical records, the database responds slowly. You examine the database options as shown in the exhibit.You want to accelerate query response time and minimize administrative overhead. How should you reconfigure the database?A．Create a SQL Server Agent job to execute the UPDATE STATISTICS statement, and schedule the job to run weekly.B．Select the Auto Update Statistics check box.C．Run the database maintenance plan wizard, and accept the default settings.D．Rebuild the primary key as a nonclustered primary key.E．Clear the Auto Create Statistics check box.
在进行移动台的级别更新时，A接口初始信令消息是（）A、CLASSMARK REQUESTB、CLASSMARK ENQUIREDC、CLASSMARK CHANGED、CLASSMARK UPDATE
You work as a database administrator for Certkiller .com. In your transaction application， you have scheduled a job to update the optimizer statistics at05：00 pm every Friday. The job has successfully completed. Which three pieces of information would you check to confirm that the statistics have been collected？（）A、Average row sizeB、Last analyzed dateC、Size of table in bytesD、Size of table in database blocksE、Number of free blocks in the free listF、Number of extents present in the table.
Your company uses SQL Server 2005. Users report that report execution is slow. You investigate and discover that some queries do not use optimal execution plans. You also notice that some optimizer statistics are missing and others are out of date. You need to correct the problem so that reports execute more quickly. Which two Transact-SQL statements should you use?（）A、 DBCC CHECKTABLE B、 ALTER INDEX REORGANIZE C、 UPDATE STATISTICS D、 CREATE STATISTICS E、 DBCC SHOW_STATISTICS F、 DBCC UPDATEUSAGE
多选题You work as a database administrator for Certkiller .com. In your transaction application， you have scheduled a job to update the optimizer statistics at05：00 pm every Friday. The job has successfully completed. Which three pieces of information would you check to confirm that the statistics have been collected？（）AAverage row sizeBLast analyzed dateCSize of table in bytesDSize of table in database blocksENumber of free blocks in the free listFNumber of extents present in the table.
多选题In your Oracle 10g database ， you have scheduled a job to update the optimizer statistics at 05：00 pm every Friday. The job has successfully completed. Which three pieces of information would you check to confirm that the statistics have been collected？（）Aaverage row sizeBlast analyzed dateCsize of table in bytesDsize of table in database blocksEnumber of free blocks in the free listFnumber of extents present in the table
单选题A revised print of a chart is made （）.Aafter every major hydrographic survey of the area covered by the chartBwhen there are numerous corrections to be made or the corrections are extensiveCwhen a low-stock situation occurs and minor corrections are madeDevery two years to update the magnetic variation information
判断题LOW上一旦出现报警，相应级别的报警按钮开始闪烁并发出声音报警，报警级别越高，报警声越持久，越响亮。A对B错